A lens actuator is used to optimize an image captured by an image capturing device of a camera by controlling the position and/or movement of a lens. For example, an auto-focusing technique can be used to bring into focus in an image the subject that the user desires to capture based on the distance between the camera and the subject. This can be realized by the displacement of the lens along the optical (lens) axis, or a z-axis, to control the distance between the lens and the image capturing mechanism. Another technique is vibration compensation control, which compensates for motion of the camera body, for example, due to the shaking of the camera. This technique typically requires the lens, or one or more of the multiple lenses in a lens module, to be moved relative to the image capturing device to cancel the motion of the camera.
U.S. Patent Application Publication No. 2006/0028320 published in the name of Osaka on 9 Feb. 2006 describes an example of an autofocus actuator. A lens actuator has a lens holder with a coil wound around the lens holder When an electric current is supplied to the coil, the magnetic field induced by the electric current through the coil interacts with that of a permanent magnet surrounding the lens holder, causing the lens holder to be displaced along the optical axis. This autofocus actuator using a coil and the magnet realises a one-dimensional movement of the lens holder to implement an autofocus function.
For the prior art, only autofocus function can be achieved. A need exists for a mechanism adapted to provide both autofocus and vibration compensation functions.